1 Purpose of settlement monitoring works
- Initially estimating the velocity of settlement in structural phase, the positions of building having greater or lesser settlement for the design company to take measures concerning
- Assessing working ability and stability of the building foundation during construction period and operation period.
2 Settlement monitoring method
- The popular method to monitor the settlement of buiding is The backsight-foresight level measurement method stipulated in The standard TCXDVN 271: 2002 “ The technical process to determine the Settlement of architectural and industriel building is The backsight-foresight level measurement method”
- The tenor of this method is to determine the level of settlement benchmarks (fixed on proper location in building) based on local level of base benchmarks by backsight-foresight level measurement method.
- The settlement monitoring is carried out in cycle, the settlement data of each benchmark in every cycle is determined by the different level between two consecutive cycle.
- In the level surveying the tolerance in the procedures of level traverse grade II shall be followed with principal norms as follows:
+ The distance of shooting is less than 30m:
+ The different distance from backsight and foresight shooting is does not exceed 2m.
However, depending on the site condition The difference of shooting may be greater;
+ The different height reading on primary and secondary scale ( or between two readings) in one station does not exceed 0.3mm;
+ The closure error shall satisfy:
fh ≤ ±0,5x
, n is the station number
− The cycle of settlement monitoring: The number of settlement monitoring depends on The characteristics of the building site, the construction schedule and the settlement feature of the building. The cycle sis caculated to reflect substantially the supporting progress of foundation and the stability of the building. The total number of cycle is 39 cycles.
3. Equipment
Using The automatic level with high accuracy NA 2 and leveling staff Invar and other automatic level which have the equivalent accuracy (as Ni 04, NAK2 or NA 03) to monitor the settlement work.
Automatic level NA-2 with Micrometter
4 Fee of the settlement monitoring work
- We will inform the exact fee for monitoring work after receiving information about the project size and exact scope of work.
Some project for our settlement monitoring works:
1. Royal Tower
